1. Field of the Invention
This invention relates generally to ground proximity warning systems and, more particularly, to a system that provides a warning to the pilot of an aircraft if the descent rate of the aircraft is excessive for the altitude at which the aircraft is flying. The criteria for determining whether or not such a warning is to be generated are alterable as a function of the configuration of the aircraft. Such a warning system is particularly useful for carrier based anti-submarine aircraft such as the Lockheed S3-A.
2. Description of the Prior Art
Systems for providing the pilot of an aircraft with a warning in the event that the aircraft is descending too rapidly are known. Examples of such systems are disclosed in U.S. Pat. Nos. 3,946,358; 3,947,808; 3,958,219 and 4,215,334, all assigned to the same assignee as the assignee of the present invention.
While all of the above systems serve the basic function of alerting the pilot if the descent rate of the aircraft exceeds a predetermined safe descent rate determined by the altitude above ground of the aircraft, the above systems are designed to operate with transport aircraft whose operational and flight conditions are such that the approach and landing conditions are readily predictable. However, for aircraft such as, for example, military and tactical aircraft whose operational and flight conditions can vary widely, systems designed for aircraft having predictable flight parameters tend to provide false or nuisance warnings where no unsafe condition actually exists, and may provide less than the desired warning times under other conditions.